| Full text | |
| Author(s): Show less - |
Benedetti, Joao P., V
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Riffel, Rogerio A.
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Ricci, Tiago
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Trevisan, Marina
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Riffel, Rogemar A.
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Pastoriza, Miriani
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Dahmer-Hahn, Luis G.
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Ruschel-Dutra, Daniel
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Rodriguez-Ardila, Alberto
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Hernandez-Jimenez, Jose A.
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Steiner, Joao
Total Authors: 11
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| Document type: | Journal article |
| Source: | Monthly Notices of the Royal Astronomical Society; v. 522, n. 2, p. 14-pg., 2023-04-21. |
| Abstract | |
We use Gemini integral field unit observations to map the stellar population properties in the inner region (similar to 680 x 470 pc(2)) of the galaxy NGC 6868. In order to understand the physical and chemical properties of the stellar content of this galaxy, we performed stellar population synthesis using the starlight code with the MILES simple stellar population models. We measured the absorption line indices Fe4383, Mg-2, Mg-b, Fe5270, and Fe5335 for the whole FoV, and used them to derive Fe3 and [MgFe]'. These indices were used to derive [alpha/Fe]. This galaxy is dominated by old metal-rich populations (12.6 Gyr; 1.0 and 1.6 Z(circle dot)) with a negative metallicity gradient. We also found a recent (similar to 63 Myr) metal-rich (1.6 Z(circle dot)) residual star formation in the centre of the galaxy. A dust lane with a peak extinction in the V band of 0.65 mag is seen. No signs of ordered stellar motion are found and the stellar kinematics is dispersion dominated. All indices show a spatial profile varying significantly along the FoV. Mg-2 shows a shallow gradient, compatible with the occurrence of mergers in the past. Mg-b and Fe3 profiles suggest different enrichment processes for these elements. We observe three distinct regions: for R< 100 pc and R > 220 pc, Mg-2, Mg-b anticorrelate with respect to Fe3 and [MgFe]', and for 100 pc < R < 220 pc, they correlate, hinting at different enrichment histories. The [alpha/Fe] profile is really complex and has a central value of similar to 0.2 dex. We interpret this as the result of a past merger with another galaxy with a different [a/Fe] history, thus explaining the [alpha/Fe] maps. (AU) | |
| FAPESP's process: | 21/08920-8 - Interacting galaxies: new catalog with data from the S-Plus survey and characterization of physical properties with data from the Survey MaNGA. |
| Grantee: | Jose Andres Hernandez Jimenez |
| Support Opportunities: | Scholarships in Brazil - Technical Training Program - Technical Training |